Reduction of br2 and cl2 in semiconductor processes

Abstract

One or more embodiments described herein relate to abatement systems for reducing Br2 and Cl2 in semiconductor processes. In embodiments described herein, semiconductor etch processes are performed within process chambers. Thereafter, fluorinated greenhouse gases (F-GHGs), HBr, and Cl2 gases exit the process chamber and enter a plasma reactor. Reagent gases are delivered from a reagent gas delivery apparatus to the plasma reactor to mix with the process gases. Radio frequency (RF) power is applied to the plasma reactor, which adds energy and “excites” the gases within the process chamber. When HBr is energized, it forms Br2. Br2 and Cl2 are corrosive and toxic. However, the addition of H2O in the plasma reactor quenches the Br2 and Cl2 emissions, as the H atoms recombine with the Br atoms and the Cl atoms to form HBr and HCl. HBr and HCl are readily water-soluble and removed through a wet scrubber.

1 . A process system, comprising
 a process chamber;   a plasma reactor located downstream of the process chamber;   a reagent gas delivery apparatus located between the process chamber and the plasma reactor;   a vacuum pump located downstream of the plasma reactor;   a wet scrubber located downstream of the vacuum pump;   an inert gas delivery apparatus located between the plasma reactor and the vacuum pump; and   a controller configured to control an operation performed in the process system, the operation comprising:
 performing a semiconductor etch process within the process chamber using process gases including fluorinated greenhouse gases (F-GHGs), HBr, and Cl 2 , wherein the process gases are configured to flow out of the process chamber into the plasma reactor; 
 introducing water vapor (H 2 O) from the reagent gas delivery system to the plasma reactor to react with the process gases; and 
 applying RF power to the plasma reactor; wherein
 a ratio of a H 2 O flow rate to a HBr flow rate is greater than 2:1; and 
 a ratio a H 2 O flow rate to a Br 2  byproduct gas is greater than 15:1. 
 
   
     
     
         2 . The process system of  claim 1 , wherein the F-GHGs include CF 4 , SF 6 , C 4 F 8 , and CHF 3 . 
     
     
         3 . The process system of  claim 1 , wherein the reagent gas delivery system is configured to supply hydrogen (H) and oxygen (O) atoms to the plasma reactor. 
     
     
         4 . The process system of  claim 3 , wherein the amount of H and O atoms are greater than the amount of F-GHGs. 
     
     
         5 . The process system of  claim 3 , wherein the amount of F-GHGs is greater the amount of H and O atoms. 
     
     
         6 . The process system of  claim 5 , wherein the amount of RF power is between about 2000 Watts and about 4000 Watts. 
     
     
         7 . The process system of  claim 1 , wherein the F-GHGs include at least one of CF 4 , SF 6 , C 4 F 8 , or CHF 3 . 
     
     
         8 . A process system, comprising:
 a process chamber;   a plasma reactor located downstream of the process chamber;   a reagent gas delivery apparatus located between the process chamber and the plasma reactor;   a vacuum pump located downstream of the plasma reactor;   a wet scrubber located downstream of the vacuum pump;   an inert gas delivery apparatus located between the plasma reactor and the vacuum pump; and   a controller configured to control an operation performed in the process system, the operation comprising:
 performing a semiconductor etch process within the process chamber using process gases including fluorinated greenhouse gases (F-GHGs), HBr, and Cl 2 , wherein the process gases are configured to flow out of the process chamber into the plasma reactor; 
 introducing a reagent vapor from the reagent gas delivery system to the plasma reactor to react with the process gases; 
 applying RF power to the plasma reactor converting the process gases at least partially to a Br 2  byproduct gas within the plasma reactor and reacting the Br 2  byproduct gas with the reagent vapor to form HBr, wherein a ratio of a reagent vapor flow rate to a HBr flow rate of the HBr gas to the process chamber is greater than 2:1; and 
 introducing an inert gas between the plasma reactor and a pump configured to pump gases exiting the plasma reactor. 
   
     
     
         9 . The process system of  claim 8 , wherein a ratio a H 2 O flow rate to a Br 2  byproduct gas is greater than 15:1. 
     
     
         10 . The process system of  claim 8 , wherein the reagent vapor includes H 2 O. 
     
     
         11 . The process system of  claim 8 , wherein the reagent vapor includes hydrogen (H) and oxygen (O) atoms. 
     
     
         12 . The process system of  claim 10 , wherein the amount of F-GHGs are greater the amount of H and O atoms. 
     
     
         13 . The process system of  claim 8 , the amount of RF power is between about 2000 Watts and about 4000 Watts. 
     
     
         14 . A process system, comprising:
 a process chamber;   a plasma reactor located downstream of the process chamber;   a reagent gas delivery apparatus located between the process chamber and the plasma reactor;   a vacuum pump located downstream of the plasma reactor;   a wet scrubber located downstream of the vacuum pump;   an inert gas delivery apparatus located between the plasma reactor and the vacuum pump; and   a controller configured to control an operation performed in the process system, the operation comprising:
 performing a semiconductor etch process within the process chamber using process gases including fluorinated greenhouse gases (F-GHGs), HBr, and Cl 2 , wherein the process gases are configured to flow out of the process chamber into the plasma reactor; 
 introducing a reagent vapor from the reagent gas delivery system to the plasma reactor to react with the process gases; 
 applying RF power to the plasma reactor converting the process gases at least partially to a HCL byproduct gas within the plasma reactor and reacting the Cl 2  byproduct gas with the reagent vapor to form HCl; and 
 introducing an inert gas between the plasma reactor and a pump configured to pump gases exiting the plasma reactor. 
   
     
     
         15 . The process system of  claim 14 , wherein the reagent vapor includes H 2 O. 
     
     
         16 . The process system of  claim 14 , wherein the reagent vapor includes hydrogen (H) and oxygen (O) atoms. 
     
     
         17 . The process system of  claim 14 , wherein the F-GHGs include at least one of CF 4 , SF 6 , C 4 F 8 , or CHF 3 . 
     
     
         18 . The process system of  claim 16 , wherein the amount of F-GHGs are greater the amount of H and O atoms. 
     
     
         19 . The process system of  claim 14 , wherein a ratio a H 2 O flow rate to a Br 2  byproduct gas is greater than 15:1. 
     
     
         20 . The process system of  claim 14 , wherein the operations further comprise pumping gases exiting the plasma reactor and the inert gas into the wet scrubber.